Power driven winch



y 2, 1956 C. A. FRENCH 2,746,718

POWER DRIVEN WINCH Filed Jan. 10, 1955 INVENTOR CHARLES A. FRENCHATTORNEY FORWARD United States Patent 2,746,718 POWER DRIVEN WINCHCharles A. French, Vancouver, British Columbia, Canada ApplicationJanuary 10, 1955, Serial No. 480,960

8 Claims. (Cl. 254-486) My invention relates to improvements in powerdriven winches.

A particular object of the invention is to provide a winch capable ofbeing connected to a power driven shaft having rotation in one directiononly.

Many trucks and trailers are equipped with a power take off shaft whichmay or may not be reversible or even provided with a satisfactory clutchby which it may be set in motion or otherwise. The invention heredescribed is particularly suited for such situations and is providedwith a single operating lever conveniently situated close to the windingdrum, whereby the winch can be instantly set to wind in or slacken ofi aload, or hold I it in any position while the primary drive shaft of thewinch continues to rotate.

Referring to the accompanying drawings:

Figure 1 is a longitudinal sectional view of the invention taken on theline 11 of Figure 2.

Figure 2 is a plan view of the invention.

In the drawings like characters of reference indicate correspondingparts in each figure.

The numeral 1 indicates a frame having a base 2 supporting spaced sidewalls 3 and 4, between which a drum shaft 5 is horizontally supported.Rotatably mounted upon the shaft 5 is a winding drum 7 having a flange Sand a ratchet wheel 9 provided with teeth 10. The wheel 9 is engagednormally by a spring loaded pawl 11 which is rockingly mounted upon apin 12 extending from the side wall 4.

Rotatably journalled in bearings 14 in the side walls 3 and 4 is a shaft15 having secured thereto a sprocket 16 which is adapted to beconstantly driven by an endless chain 17 from a suitable source ofpower, not shown. The driven shaft 15 is fitted with two eccentrics 19and 20 which are secured to said shaft one hundred and eighty degreesapart and these eccentrics rockingly carry two driving pawlsrespectively numbered 21 and 22, both of which are spring loaded withleaf springs 24 carried by a transverse member 25 to normally keep thedriving pawls in contact with the ratchet teeth 10. The pawl 22 islonger than the pawl 21 by an amount equal to half the length of a tooth10.

A horizontal shaft 27 is carried between the side wall 4 and a bearing28 on the base 2 of the winch frame and is fitted with an operatinglever 30 which is mounted on the outside of the wall 4. The shaft 27 isfitted with two dogs 32 and 33 which may be selectively moved by thelever 30 to engage lugs 35 and 36 respectively on the lower ends of thedriving pawls 21 and 22 to swing said pawls rearwardly away fromengagement with the ratchet wheel 9.

A bell crank 38 is rockingly mounted on the wall 4 and is provided withone leg 40 on the inner side of the wall and a downwardly turned leg 41,shown in dotted line on the outside of the wall. to rest normally on theshank 43 of the spring loaded pawl 11 and the leg 41 is normally engagedby the upper end of a rocking lever 45 which is pivotally mount The leg40 is adapted v ed as at 46 on the outside of the wall 4, as is shown indotted line in Figure 1. The lever is provided with .a pin 47 at itslower end which is adapted to be engaged by the operating lever 30 whensaid lever is swung to its uppermost or Reverse position. as shown inFigure 1. The eccentrics 19 and 20 each have a stroke of half the lengthof a tooth 10 of the ratchet wheel 9, consequently when the driven shaft15 is rotating it will take one revolution of said shaft to rotate thedrum to the extent of one ratchet tooth. When the shaft is running andthe operating lever 30 is in the full line or .Forward position'shown inFigure l, neither of the lugs 35 or 36 will be engaged by theirrespective dogs, so that half one rotation of the shaft will cause thepawl 21 to move the ratchet wheel one half tooth and the second halfrotation will cause the pawl 22 to engage the same tooth and raise itthe second half of its length. The locking pawl 11 will obviously droponto the next lower tooth to hold the wheel against return movement.

If, when raising a load, the operating lever 30 is raised to theintermediate or neutral position, the dog 33 will be moved into aposition relative to the lug 36 to prevent the pawl from seating ontothe ratchet wheel below the end of a tooth 10, so that no advancement ofthe wheel takes place. When the lever 30 is raised to its uppermost orReverse position both pawls 21 and 22 Will be affected by the dogs 32and 33 which have been moved by the raising of the lever to itsuppermost position into the normal path of the lugs 35 and 36. Theobstruction to the free movement of the pawls causes each one of saidpawls 21 and 22 to withdraw alternately in an arcuate path having theend of its lug 35 or 36 as a fulcrum as each of the said pawls reachesits lowermost position. The point of each pawl on withdrawing from thetooth will be freely carried upwards by the eccentric movement until itis above the abutment of the tooth 10 and will be then urged into itsperiphery ready to slide up and engage the face of the tooth next abovebefore the complementary pawl 21 or 22 is entirely. carried out of toothengagement as above recited. 'This movement is continued with thelowermost pawl pulling away from the next tooth above as the uppermostpawl moves downwardly, holding the ratchet wheel against free rotationin a clockwise direction. During the above described movement of thelever 30 said lever would have come into engagement with the pin 47 ofthe rocking lever 45 to move it slightly in a clockwise direction andcause the bell crank 38 to rock and raise the spring loaded pawl 11 fromits position of engagement upon a tooth 10 of the ratchet wheel 9, sothat said wheel will be free to rotate in a clockwise direction step bystep as the pawls 21 and 22 move downwardly in contact with the teeth ofsaid ratchet wheel. It will be understood that the normal pull on thecable is relied upon to rotate the drum 7 in a reverse or clockwisedirection when the pawls 21 and 22 are withdrawn from operativeengagement with the ratchet wheel 9. e

What I claim as my invention is:

1. A winch comprising a freely rotatable drum having a ratchet wheelwith teeth connected therewith, a pawl normally engaging the ratchetwheel to hold it against reversal, a driven shaft mounted for constantrotation in one direction, a pair of eccentrics mounted upon said shaft,a driving pawl swingingly mounted upon each eccentric and normallyengaging said ratchet wheel to rotate said wheel one tooth in onedirection as the eccentric shaft is rotated one revolution, and manuallyoperable means to alternately free the pawls from the teeth of theratchet wheel whereby said ratchet wheel may turn in a reverse directionwhile the shaft continues to rotate in the one direction.

2. A winch as claimed in claim 1 and manually operable means fordisengaging one of the driving pawls from the ratchet wheel teeth at thestart of its driving stroke.

3. A winch as claimed in claim 1 and manually opcrable means fordisengaging both of the driving pawls from the ratchet wheel teeth atthe start of their driving strokes. 4. A winch comprising a freelyrotatable drum having a ratchet wheel with teeth connected therewith, adriven shaft mounted for constant rotation in one direction, a pair ofeccentrics mounted upon said shaft, a driving pawl swingingly mountedupon each eccentric and normally engaging said ratchet wheel to rotatesaid wheel one tooth in one direction as the eccentric shaft is rotatedone revolution, and spring loaded means normally holding the ratchetwheel against rotation in a reverse direction, and manually operablemeans for disengaging one of the driving pawls from the ratchet wheelteeth.

5. A winch comprising a freely rotatable drum having a ratchet wheelwith teeth connected therewith, a driven shaft mounted parallel to saiddrum and adapted for constant rotation in one direction, a pair ofeccentrics mounted upon said shaft, a driving pawl swingingly mountedupon each eccentric, spring means normally urging said pawls intoengagement with said teeth to rotate said wheel, a holding pawl normallyengaging said teeth, manually operable means for selectively disengagingthe driving pawls from the teeth, and means operable by the manuallyoperable means for disengaging the holding pawl to release the ratchetto rotate in step by step movement against the driving pawls as thedriven shaft continues to rotate in its normal direction.

6. A winch comprising a freely rotatable drum having a ratchet wheelwith teeth connected therewith, a driven shaft mounted parallel to saiddrum and adapted for constant rotation in one direction, a pair ofeccentrics mounted upon said shaft, a driving pawl swingingly mountedupon each eccentric, spring means normally urging said pawls intoengagement with said teeth to rotate said wheel, a holding pawlresiliently engaging said teeth, an operative shaft having a pair ofdogs aligned with the pawls, each of said pawls having a lug, saidoperative shaft being adapted to be rocked to selectively dispose thedogs in the path of the lugs to rock the pawls out of engagement withthe teeth, and means operable in response to movement of the operativeshaft for disengaging the holding pawl while the driven shaft continuesto rotate in its one direction.

7. A winch as claimed in claim 6, said pawls having a stroke equal tohalf the length of a ratchet tooth and one of said pawls exceeding theother in length by half the length of a ratchet tooth.

8. A winch comprising a freely rotatable drum having a ratchet wheelwith teeth connected therewith, a driven shaft, a holding pawl adaptedto engage the teeth of the ratchet wheel, a pair of eccentrics on thedriven shaft and a driving pawl in each eccentric adapted to engage theteeth of the ratchet wheel, a single operating lever having means forselectively engaging the pawls to disengage them from the ratchet wheelteeth, and means engageable by the lever for disengaging the holdingpawl from engagement with the ratchet wheel teeth, said lever beingselectively movable to three positions, one position leaving the pawlsto engage the wheel in a direction to raise a load, a second positionbeing tocause one driving pawl to disengage the ratchet wheel wherebymovement less than the length of a ratchet wheel tooth is imparted tothe wheel and a third position whereby the means for selectivelyengaging the pawls will cause the driving pawls to disengage the ratchetwheel before reaching an end of their stroke and to cause each pawl torelease a tooth when reaching the opposite end of the stroke, therebyreleasing the. ratchet wheel to rotate to lower a load, said loadraising, load holding and load lowering being effected while the drivenshaft is rotating in one direction.

References Cited in the file of this patent UNITED STATES PATENTS 54,467Goodsell et al May 1, 1866 1,209,917 Westinghouse Dec. 26, 19162,670,176 Cofling Feb. 23, 1954

